The present invention relates to a tourniquet-type device for stanching the flow of blood from a punctured vein or artery to induce hemostasis and, more particularly, to a radial artery clamp for inducing hemostasis in the radial artery of the arm.
Several tourniquets are disclosed in the patent literature. Dunton U.S. Pat. No. 37,156 discloses an adjustable tourniquet including pressure pads for arresting arterial circulation through a limb without applying pressure to other portions of a limb. Gilman U.S. Pat. No. 3,884,240 discloses a tourniquet having a U-shaped spring steel loop to which a pair of pads are mounted. A pressure screw is disposed at one end of the loop for permitting the operator to adjust the position of one of the pads.
Snow U.S. Pat. No. 4,557,262 discloses a dialysis clamp having a spring loaded pressure pad. Royce U.S. Pat. No. 4,572,182 discloses a stand-mounted artery clamp which is especially adapted for applying pressure to the femoral artery. Also of interest is Loving U.S. Pat. No. 4,314,568. Although Loving does not disclose a device for inducing hemostasis in a punctured artery, it does disclose a device for stabilizing the position of a vein prior to venipuncture, so that the clinician can insert a needle into the vein more easily.
Although the above discussed references disclose devices which are useful in performing their intended functions, all apply pressure over a relatively large area of the limb of a patient. In particular, a need exists for a device for achieving hemostasis in the radial artery of the arm upon withdrawal of a needle or intravenous tube, while permitting continued circulation through the ulnar artery.
The lower arm includes two main arteries, the radial artery and the ulnar artery which are the primary arteries for delivering blood to the lower arm and hand of a human being. The radial and ulnar arteries are companion arteries, both originating at the distal end of the brachial artery, near the elbow, and extending in a generally parallel relation along the lower arm from the elbow to the proximal part of the palm of the hand.
The radial artery may be punctured to draw blood, to perform certain blood tests, or to introduce various types of intravenous fluid into the blood stream. One test which utilizes blood drawn from the radial artery is an arterial blood gas analysis. In order to ensure accurate results, it is important to perform the blood gas analysis on the blood sample soon after the sample is drawn.
The clinician drawing the sample must ensure that hemostasis has been induced in the puncture in the radial artery before he is free to deliver the blood sample to the laboratory. Currently, hemostasis is typically induced by the clinician manually applying pressure over the puncture site for 3 to 15 minutes, however. It will be appreciated that this delay is undesirable, therefore, as the test results may be affected.
A second procedure involving the puncture of the radial artery involves the use of an indwelling intravenous line which is inserted into the radial artery. When the intravenous line is removed from the artery, pressure must be placed on the puncture site to induce hemostasis. The typical procedure requires that pressure be applied manually for about 20 to 30 minutes to the puncture site by a nurse before hemostasis is induced. Clearly, this requires an excessive amount of time for the attending nurse.
It will be appreciated that the nurse or technician would be helped greatly by a device which could be placed over the puncture site to apply pressure, thereby eliminating the need to apply pressure manually, and allowing the nurse or technician to perform other duties.
Although it is necessary to apply pressure over the puncture site to induce hemostasis, this pressure should preferably be applied selectively. Specifically, it is desirable to apply pressure over the puncture site in the radial artery, while not applying sufficient pressure over the ulnar artery to restrict the flow of blood in the ulnar artery to the lower arm and hand. For this reason, the use of prior art tourniquet devices has not been used for this procedure.
It is seen that there is a need for a device which can apply pressure over a puncture wound in a radial artery and induce hemostasis, while allowing the substantially unrestricted flow of blood through the ulnar artery.